Recent studies indicate that alcohol consumption is regulated by several interacting neurotransmitters, including the dopamine and serotonin systems. In a randomized double-blind design, chronic alcoholic outpatients received L-DOPA or L-5-hydroxytrytophan, both with the peripheral decarboxylase inhibitor carbidopa or placebo for a one year period. During this year, alcohol consumption, liver function, craving for alcohol, mental status, psychosocial functioning, and compliance with medication were assessed at regular intervals. Prior to entry into the study, after 3 months, and at one year, the following procedures were conducted to measure drug effects: (1) behavioral evaluation; (2) determination of concentrations of drugs, monomanias, hormones, and peptides in blood and cerebrospinal fluid; (3) orthostatic changes in heart rate, blood pressure, and plasma norepinephrine concentrations; and (4) assessment of plasma vasopressin response to saline infusion. Changes in alcohol consumption will be related to biochemical and behavioral parameters.